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Tytuł:
Neptunian dykes in the Middle Miocene reefs of western Ukraine : preliminary results
Autorzy:
Jasionowski, M.
Peryt, D.
Peryt, T. M.
Powiązania:
https://bibliotekanauki.pl/articles/2060499.pdf
Data publikacji:
2012
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Sarmatian
foraminifers
reefs
sedimentology
palaeoenvironments
Ukraine
Opis:
Neptunian dykes were recently recorded within the Middle Miocene (Upper Badenian and Lower Sarmatian) Medobory reef complex of the Carpathian Foreland in western Ukraine. The Upper Badenian reefs are cut by a regular, semi-perpendicular network of intersecting fissures that penetrate the Badenian reef limestone down for more than 10 m. The dykes are filled by several generations of Sarmatian microbialites coating the fracture walls and by bedded bioclastic sediment (including foraminifers) which is more important volumetrically. The fissure fillings containing both the Sarmatian material as well as rare clasts of Badenian rocks indicate that the fissures were open during the onset of Sarmatian deposition. They originated following the emergence and fracturing of the Badenian limestones, either due to fault tectonics at basin margins induced by basin subsidence, around the Badenian-Sarmatian boundary, or to gravitational instability of large lithified Badenian reef bodies. Only one phase of fracture opening occurred. The filling of fractures was episodic, with pulses of cementation and microbial growth and sediment injection. Four different foraminiferal assemblages recorded in the neptunian dykes indicate that the process of fracture filling was long-lasting.
Źródło:
Geological Quarterly; 2012, 56, 4; 881--894
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polyphase dolomitization of the Wuchiapingian Zechstein Limestone (Ca1) isolated reefs (Wolsztyn Palaeo-Ridge, Fore-Sudetic Monocline, SW Poland)
Autorzy:
Jasionowski, M.
Peryt, T. M.
Durakiewicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/2060044.pdf
Data publikacji:
2014
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Zechstein Limestone
reefs
diagenesis
dolomitization
carbon and oxygen isotopes
Opis:
Dolomitisation was the main diagenetic process in the Upper Permian Zechstein Limestone of the Wolsztyn High-dolomite cementation (“over-dolomitisation”) also occurred. The rocks studied usually have a mixed mineralogy and represent a continuous spectrum from pure limestone to pure dolomite. This is due to varying degrees of dolomitisation, dolomite cementation and dedolomitisation. There are two main types of dolomite: replacement dolomite (mostly planar unimodal dolosparite mosaics that are mainly fabric-destructive) and cement dolomite (planar isopachous rims and pore-filling non-planar saddle-dolomite crystals). The timing of dolomitisation and dolomite cementation is difficult to ascertain, but comparing petrographical and geochemical data indicates that the reef carbonates were dolomitised shortly after deposition in a near-surface sabkha/seepage-reflux and then in burial systems. It seems that many of the dolomites gain their present isotopic composition when buried in relatively high-temperature conditions, as shown by low oxygen isotopic ratios ( δ18O as low as –9‰ PDB) and the presence of saddle dolomite. No isotopic support for a water-mixing mechanism is documented.
Źródło:
Geological Quarterly; 2014, 58, 3; 503--520
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamika rozwoju utworów koralowych środkowego oksfordu okolic Bałtowa
Middle Oxfordian coral facies of the Bałtów region, NE margin of the Holy Cross Mts, Poland
Autorzy:
Gutowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2077305.pdf
Data publikacji:
2004
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
rafa
utwory koralowe
Bałtów
coral facies
reefs
syndepositional activity of extensional blocks
Opis:
Coral facies developed on the Middle Oxfordian carbonate ramp were controlled in the region of Bałtów, NE margin of the Holy Cross Mts., Poland, by syndepositional activity of extensional fault blocks. Elevated parts of sea bottom were occupied since Early Oxfordian time by sponge bioherms successively colonized by coral reefs when grown up to the sea level. Micritic sedimentation prevailed in interbioherm denivelations. This micritic succession was replaced by soft-bottom coral buildups constructed by flat coral colonies, typical of a relatively quiet environment of the depths 20-70 m, and finally by coarse bioclastic grainstones and oncolites which are interpreted as talus of the coral reef constructed on tops of former sponge bioherms by branched and hemispherical coral colonies in very dynamic and extremely shallow water conditions.
Źródło:
Volumina Jurassica; 2004, 2, 1; 17-28
1896-7876
1731-3708
Pojawia się w:
Volumina Jurassica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxfordian to Valanginian palaeoenviron- mental evolution on the western Moesian Carbonate Platform: a case study from SW Bulgaria
Autorzy:
Ivanova, D.
Kołodziej, B.
Koleva-Rekalova, E.
Roniewicz, E.
Powiązania:
https://bibliotekanauki.pl/articles/191387.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Oxfordian-Valanginian
biostratigraphy
carbonate sedimentology
reefs
Moesian Platform
Lyubash unit
Bulgaria
Opis:
Three sections (Rebro, Lyalintsi and Velinovo) of the Upper Jurassic-Lower Cretaceous carbonate sequences from the Lyubash unit (Srednogorie, Balkanides, SW Bulgaria) have been studied for elucidation of biostratigraphy and palaeoenvironmental evolution. Palaeontological studies of foraminifera, supplemented by studies of calcareous dinoflagellate cysts and corals, enabled the determination of the Oxfordian-Valanginian age of the analysed sequences. They were deposited on the Dragoman Block (western part of the Moesian Platform), and during Mid-Late Cretaceous included to the Srednogorie. A possible Middle to Late Callovian age of the lowermost part (overlying the Bajocian-Lower Bathonian Polaten Formation) of the studied sections assumed till now has not been confirmed by the present studies. Eleven facies have been distinguished and attributed to depositional environments. Marine sedimentation on a homoclinal ramp started in the Oxfordian and till the Early Kimmeridgian - in all three sections - was dominated by fine-grained peloidal-bioclastic wackestones to grainstones. Since the Late Kimmeridgian, when a rimmed platform established, facies pattern underwent differentiation into (i) the inner platform (lagoon and tidal flat facies) - only in Velinovo, (ii) reef and peri-reef facies/bioclastic shoals - mainly in Lyalintsi, and (iii) platform slope - mainly in Rebro. Sedimentation generally displays a shallowing-upward trend. Two stages in evolution of the rimmed platform are postulated. The mobile stage lasting till the Tithonian/Berriasian boundary was followed by a more stable stage in the Berriasian to Valanginian time. Reefs are developed mainly as coral-microbial biostromes, lower coral bioherms or coral thickets, in the environment of moderate energy and sedimentation. They contain highly diversified corals (72 species). Micro- bialites contributed to the reef framework, but they never dominated. Locally, microencrusters and cement crusts formed important part of reefal framework. During the mobile stage of the platform evolution a relative sea-level rise interrupted reef development, as evidenced by intercalations of limestones with Saccocoma. During the second stage high carbonate production and/or regressive eustatic events, not balanced by subsidence, decreased accommodation space, limiting reef growth and enhancing carbonate export to distal parts of the platform.
Źródło:
Annales Societatis Geologorum Poloniae; 2008, 78, No 2; 65-90
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A lost carbonate platform deciphered from clasts embedded in flysch: Štramberk-type limestones, Polish Outer Carpathians
Autorzy:
Hoffmann, Mariusz
Kołodziej, Bogusław
Kowal-Kasprzyk, Justyna
Powiązania:
https://bibliotekanauki.pl/articles/1835996.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
reefs
facies
Štramberk Limestone
Silesian Ridge
Jurassic
Cretaceous
Carpathian Basin
Polska
Opis:
Limestones designated the Štramberk-type are the most common carbonate exotic clasts (exotics) embedded in the uppermost Jurassic–Miocene flysch deposits of the Polish Outer Carpathians. About 80% of stratigraphically determinable carbonate exotics from the Silesian, Sub-Silesian and Skole units (nappes) are of Tithonian (mostly)–Berriasian (sporadically Valanginian) age. A study of these exotics revealed eight main facies types: coral-microbial boundstones (FT 1), microencruster-microbial-cement boundstones (FT 2), microbial and microbial-sponge boundstones (FT 3), detrital limestones (FT 4), foraminiferal-algal limestones (FT 5), peloidalbioclastic limestones (FT 6), ooid grainstones (FT 7), and mudstones-wackestones with calpionellids (FT 8). Štramberk-type limestones in Poland and the better known Štramberk Limestone in the Czech Republic are remnants of lost carbonate platforms, collectively designated the Štramberk Carbonate Platform. Narrow platforms were developed on intra-basinal, structural highs (some of them are generalized as the Silesian Ridge), with their morphology determined by Late Jurassic synsedimentary tectonics. An attempt was made to reconstruct the facies distribution on the Tithonian–earliest Cretaceous carbonate platform. In the inner platform, coral-microbial patch-reefs (FT 1) grew, while the upper slope of the platform was the depositional setting for the microencruster-microbial-cement boundstones (FT 2). Microbial and microbial-sponge boundstones (FT 3), analogous to the Oxfordian–Kimmeridgian boundstones of the northern Tethyan shelf (also present among exotics), were developed in a deeper setting. In the inner, open part of the platform, foraminiferal-algal limestones (FT 5) and peloidal-bioclastic limestones (FT 6) were deposited. Poorly sorted, detrital limestones (FT 4), including clastsupported breccias, were formed mainly in a peri-reefal environment and on the margin of the platform, in a high-energy setting. Ooid grainstones (FT 7), rarely represented in the exotics, were formed on the platform margin. Mudstones-wackestones with calpionellids (FT 8) were deposited in a deeper part of the platform slope and/or in a basinal setting. In tectonic grabens, between ridges with attached carbonate platforms, sedimentation of the pelagic (analogous to FT 8) and allodapic (“pre-flysch”) Cieszyn Limestone Formation took place. The most common facies are FT 4 and FT 1. Sedimentation on the Štramberk Carbonate Platform terminated in the earliest Cretaceous, when the platform was destroyed and drowned. It is recorded in a few exotics as thin, neptunian dykes (and large dykes in the Štramberk Limestone), filled with dark, deep-water limestones. Reefal facies of the Štramberk Carbonate Platform share similarities in several respects (e.g., the presence of the microencrustermicrobial-cement boundstones) with reefs of other intra-Tethyan carbonate platforms, but clearly differ from palaeogeographically close reefs and coral-bearing facies of the epicontinental Tethyan shelf (e.g., coeval limestones from the subsurface of the Carpathian Foredeep and the Lublin Upland in Poland; the Ernstbrunn Limestone in Austria and Czech Republic). Corals in the Štramberk Limestone and Štramberk-type limestones are the world’s most diverse coral assemblages of the Jurassic–Cretaceous transition. The intra-basinal ridge (ridges), traditionally called the Silesian Cordillera, which evolved through time from an emerged part of the Upper Silesian Massif to an accretionary prism, formed the most important provenance area for carbonate exotic clasts in the flysch of the Silesian Series. They are especially common in the Lower Cretaceous Hradiště Formation and the Upper Cretaceous–Paleocene Istebna Formation. The Baška-Inwałd 204 M. HOFFMANN Et Al. In the Polish Outer Carpathians, shallow-water carbonate sedimentation is recorded only by carbonate clasts, redeposited bioclasts, and very rare, small, unrooted, poorly exposed klippen. Clasts of limestones are exotic to the dominant siliciclastic, uppermost Jurassic–Miocene flysch deposits. They were derived from extrabasinal and intra-basinal source areas of the Carpathian rocks, which periodically emerged and were destroyed. Such rocks were described as “exotic” since the 19th century (“exotischen Graniten”, “exotische Blöcke”; Morlot, 1847; Hohenegger, 1861). In the general geological literature, the term “exotic clasts” is usually used (Flügel, 2010, p. 172), whereas in the Polish geological literature, the term “exotics” (Polish “egzotyki” including also carbonate exotics), is also commonly applied. On the basis of fossils, facies and microfacies, these clasts (pebbles, rarely blocks) are mostly described as Devonian–Carboniferous (Malik, 1978, 1979; Burtan et al., 1983; Tomaś et al., 2004) and Upper Jurassic–lowermost Cretaceous (the present paper and references therein), more rarely Middle Jurassic (Książkiewicz, 1935, 1956a; Barczyk, 1998; Olszewska and Wieczorek, 2001), Early Cretaceous (Oszczypko et al., 1992, 2006, 2020; Krobicki et al., 2005), Late Cretaceous (Książkiewicz, 1956a; Gasiński, 1998) and Palaeogene in age (Leszczyński, 1978; Rajchel and Myszkowska, 1998; Leszczyński et al., 2012; Minor-Wróblewska, 2017). At the beginning of these studies, the focus was on small, unrooted klippen, namely the Andrychów Klippen (called also Klippes) near Wadowice (Zeuschner, 1849; Hohenegger, 1861; Uhlig, 1904; Książkiewicz, 1935, 1971b; Nowak, 1976; Gasiński, 1998; Olszewska and Wieczorek, 2001), and in Kruhel Wielki, near Przemyśl (Niedźwiedzki, 1876; Wójcik, 1907, 1913, 1914; Bukowy and Geroch, 1956; Morycowa, 1988; Olszewska et al., 2009), now poorly exposed. Subsequently, exotic pebbles, much more common and providing data on more facies, were studied more frequently. The first attempt to describe exotics, including crystalline rocks, was presented by Nowak (1927). Jurassic–Cretaceous carbonate exotics at Bachowice, containing facies unknown at other localities in the Polish Outer Carpathians, were described by Książkiewicz (1956a). The preliminary results of studies, which encompassed the entire spectrum of carbonate exotics from the western part of the Polish Outer Carpathians, were presented by Burtan et al. (1984). Malik (1978, 1979) described both Palaeozoic and Mesozoic carbonate clasts in the Hradiště Sandstone of the Silesian Unit, but other studies were mostly concerned with the Štramberk-type limestones from selected outcrops. The studies of these limestones, if concerned with exotics at many localities, were focused on their fossil content (e.g., Kołodziej, 2003a; Bucur et al., 2005; Ivanova and Kołodziej, 2010; Kowal-Kasprzyk, 2014, 2018) or presented only the preliminary results of facies studies (e.g., Hoffmann and Kołodziej, 2008; Hoffmann et al., 2008). Carbonate platforms, the existence of which was deciphered from detrital carbonate components, are called lost carbonate platforms (e.g., Belka et al., 1996; Flügel, 2010; Kukoč et al., 2012). Clasts and other shallowwater components are, metaphorically, witnesses to lost carbonate factories (the term is taken from Coletti et al., 2015). Analyses of the age and lithology of exotic clasts have been applied in the reconstruction of the provenance areas of the clasts and their palaeogeography and the development of the sedimentary sequences of the Polish Outer Carpathians (e.g., Książkiewicz, 1956b, 1962, 1965; Unrug, 1968; Oszczypko, 1975; Oszczypko et al., 1992, 2006; Hoffmann, 2001; Krobicki, 2004; Słomka et al., 2004; Malata et al., 2006; Poprawa and Malata, 2006; Poprawa et al., 2006a, b; Strzeboński et al., 2017; Kowal-Kasprzyk et al., 2020). Štramberk-type limestones are most common among the exotics. It is a field term that refers to limestones, mostly beige in colour, that are supposed to be the age and facies equivalents of the Tithonian–lower Berriasian Štramberk Limestone in Moravia (Czech Republic; Eliáš and Eliášová, 1984; Picha et al., 2006). The Štramberk Limestone and the Štramberk-type limestones of both countries were deposited on platforms, attached to the intrabasinal ridges and margins of the basin of the Outer Carpathians. These platforms are collectively termed the Štramberk Carbonate Platform. The terms “Štramberk Limestone” and “Štramberk-type limestones” have been widely used in the area of the former Austro-Hungarian Empire for the field description of shallow-water limestones of assumed Late Jurassic age, usually occurring within flysch deposits of the Outer Carpathians. Upper Jurassic–lowermost Cretaceous shallow-water limestones in Romania (commonly forming mountains or ridges, e.g., Pleş et al., 2013, 2016), in Bulgaria and Serbia (Tchoumatchenco et al., 2006), and Ukraine (Krajewski and Schlagintweit, 2018), and in Turkey (Masse et al., 2015) sometimes are referred to as the Štramberk-type limestones as well. In the Austrian-German literature similar limestones in the Alps are known as the Plassen Limestone (e.g., Steiger and Wurm, 1980; Schlagintweit et al., 2005). Biostratigraphic studies revealed that some carbonate clasts, accounting for several percent of the exotics and commonly Ridge and the Sub-Silesian Ridge were the source areas for clasts from the Silesian and Sub-Silesian units (e.g., in the Hradiště Formation), while the Northern (Marginal) Ridge was the source for clasts from the Skole Unit (e.g., in the Maastrichtian–Paleocene Ropianka Formation).
Źródło:
Annales Societatis Geologorum Poloniae; 2021, 91, 3; 203-251
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sedimentary history and biota of the Zechstein Limestone (Permian, Wuchiapingian) of the Jabłonna Reef in Western Poland
Autorzy:
Peryt, T. M.
Raczyński, P.
Peryt, D.
Chłódek, K.
Mikołajewski, K.
Powiązania:
https://bibliotekanauki.pl/articles/191254.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Wuchiapingian
reefs
Zechstein
bryozoans
stromatolites
aragonite cementation
neptunian dykes
carbon and oxygen isotopes
Opis:
The Jabłonna Reef, one of the reefs formed in Wuchiapingian time in the western part of the Wolsztyn palaeo-High (SW Poland), is characterized by quite irregular outlines and consists of three separate reef bodies (ca. 0.5–1.5 km2 each; the thickness of the reef complex is usually >60 m). It is penetrated by four boreholes, which show two distinct phases of bryozoan reef development during deposition of the the Zechstein Limestone. The first one occurred early in the depositional history and botryoidal aragonitic cementation played a very important role in reef formation. This phase of bryozoan reef development terminated suddenly; one possible reason was that a relative change of sea level – first a fall and then a rise – disturbed the upwelling circulation. Consequently, bioclastic deposition predominated for a relatively long time until the second phase of bryozoan reef development occurred, but the latter was not accompanied by dubious early cementation. During this second phase, reticular fenestellid bryozoans were predominant. Subsequently, microbial reefs developed and abound in the upper part of the Zechstein Limestone sections. The general shallowing-upward nature of deposition in the Jab³onna Reef area resulted in reef-flat conditions with ubiquitous, microbial deposits, in the central part of the Jab³onna Reef. Then, the reef-flat started to prograde and eventually the entire Jab³onna Reef area became the site of very shallow, subaqueous deposition. Five biofacies are distinguished in the Jab³onna Reef sections: the Acanthocladia biofacies at the base, then mollusc-crinoid, brachiopod-bryozoan, Rectifenestella and at the top, stromatolite biofacies. They represent a shallowing-upward cycle, possibly with some important fluctuation recorded as the distinctive lithofacies boundary, corresponding to the Acanthocladia/mollusc-crinoid biofacies boundary. The 13C curves of the Jab³onna 2 and Jab³onna 4 boreholes permit correlation of the trends in the middle parts of both sections and confirm the strong diachroneity of the biofacies boundaries, with the exception of the roughly isochronous Acanthocladia/ mollusc-crinoid biofacies boundary. The presence of echinoderms and strophomenid brachiopods indicates that until deposition of the lower part of the Rectifenestella biofacies, conditions were clearly stenohaline. The subsequent elimination of stenohaline organisms and progressively poorer taxonomic differentiation of the faunal assemblage are characteristic for a slight, gradual rise in salinity. The taxonomic composition of organisms forming the Jab³onna Reef shows a similarity to reefs described from England and Germany, as well as the marginal carbonate platform of SW Poland. Filled fissures were recorded in the lower part of the Jabłonna Reef. The aragonite cementation recorded in some fissure fillings implies that they originated in rocks exposed on the sea floor and are neptunian dykes.
Źródło:
Annales Societatis Geologorum Poloniae; 2016, 86, 4; 379-413
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Facje i geochemia dolnosarmackich raf z północnych obrzeży Paratetydy na Roztoczu (Polska) i Miodoborach (Ukraina): implikacje paleoorodowiskowe
Facies and geochemistry of Lower Sarmatian reefs along the northern margins of the Paratethys in Roztocze (Poland) and Medobory (Ukraine) regions: paleoenvironmental implications
Autorzy:
Jasionowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2074462.pdf
Data publikacji:
2006
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
rafy sarmackie
facje
geochemia
paleośrodowisko
zapadlisko przedkarpackie
Paratethys
Carpathian Foredeep
Sarmatian
reefs
microbialite
serpulid
paleoenvironment
Opis:
The Middle Miocene (Lower Sarmatian = Middle Serravallian) carbonate buildups called “serpulid-microbialite reefs” that occur in the Medobory and Roztocze regions (Paratethys Basin, western Ukraine and southeastern Poland) are composed mainly of calcite precipitates. Skeletal organisms represented by serpulid tubes and bryozoans (in places) are of minor importance and comprise merely a few percent of the rock volume. They are overgrown with micritic peloidal microbialites that are the major reef component. The microbialites and serpulids/bryozoans make together a porous reef framework that is usually filled up with abundant synsedimentary fibrous cements and micritic internal sediments. Other biota is taxonomically impoverished but often rich in individuals and comprises few species of bivalves, gastropods, benthic foraminifers. In places, the serpulid-microbialite limestone masses are incrusted with coralline algae, bryozoans and nubeculariid foraminifers. Bivalve coquinas, bioclastic limestones, breccias and conglomerates are associated with the reefs. The synsedimentary precipitates represented by microbialites and fibrous cements have quite unusual geochemical characteristics. They are composed of Mg-calcite with 5–6 mole % MgCO3 in average with a very high content of strontium (1000–1650 ppm Sr). The precipitates are enriched in heavy oxygen and carbon isotopes. Fibrous cements exhibit the highest values (18O ca. +1.5 [PDB] and 13C 2.8 [PDB]. It is generally believed that in the Early Sarmatian the Paratethys was a brackish basin due to restricted connections to theWorld Ocean. This is indicated by taxonomically poor biotic assemblages that inhabited the basin. On the other hand, however, the predominance of calcitic precipitates (such as microbialites and synsedimentary cements) is indicative of water highly supersaturated in respect to calcite due to high carbonate alkalinity content. Oxygen isotopic composition of the precipitates indicates that the brackish water, in which the reefs originated, had to be enriched in the heavy oxygen isotope due to strong evaporation. The low Mg content in calcite (if compared to modern tropical settings) could be the result of a relatively low precipitation temperature coupled with lower Mg/Ca ratio in Miocene than today, and the elevated Sr content may be indicative of a high precipitation rate resulting from high supersaturation. It seems therefore that the origin of the serpulid-microbialite buildups is related to a peculiar interplay of regional and local controls in the Sarmatian Paratethys. First, the relative isolation of the entire Paratethys basin resulted in the brackish water environment that could be inhabited by taxonomically poor opportunistic biota only and simultaneously enabled blooming of microbial communities. Second, a strong evaporation of the brackish water with high alkalinity content caused a supersaturation in respect to calcium carbonate and consequently a widespread precipitation of calcite (including calcification of microbial mats).
Źródło:
Przegląd Geologiczny; 2006, 54, 5; 445-454
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Depositional environments, facies and diagenesis of the Upper Jurassic–Lower Cretaceous carbonate deposits of the Buila-Vânturariþa Massif, Southern Carpathians (Romania)
Autorzy:
Pleş, G.
Bucur, I. I.
Săsăran, E.
Powiązania:
https://bibliotekanauki.pl/articles/191844.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Carbonate platforms
reefs
microfacies
micro-encrusters
carbonate diagenesis
Upper Jurassic
lowermost Cretaceous
Southern Carpathians
Romania
Opis:
The Buila-Vânturariţa Massif consists of massive Upper Jurassic reef limestones (Kimmeridgian–Tithonian) and Lower Cretaceous (Berriasian–Valanginian, and Barremian–?Lower Aptian) deposits. Besides corals and stromatoporoids, a wide range of micro-encrusters and microbialites has contributed to their development. In this study, the authors describe briefly and interpret the main facies associations and present the microfossil assemblages that are important for age determination. The distribution of facies associations, corroborated with the micropalaeontological content and early diagenetic features, indicate different depositional environments. The carbonate successions show the evolution of the Late Jurassic–Early Cretaceous depositional environments from slope and reef-front to internal-platform sedimentary settings, including peritidal environments in the lowermost Cretaceous. Early diagenesis, represented by synsedimentary cementation in the form of micritization (including cement crusts in the reef microframework), followed by dissolution, cementation and dolomitization in a meteoric regime, and void-filling late cementation during the burial stage.
Źródło:
Annales Societatis Geologorum Poloniae; 2016, 86, 2; 165-183
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sarmatian foraminiferal assemblages of cavern fillings in the Badenian reefs of Medobory (Polupanivka, Western Ukraine)
Zespoły otwornic sarmackich z wypełnień kawern w badeńskich rafach Miodoborów (Połupaniwka, zachodnia Ukraina)
Autorzy:
Peryt, D.
Jasionowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2085905.pdf
Data publikacji:
2012
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Middle Miocene
Sarmatian
foraminifers
aberrant forms
reefs
palaeoenvironments
Ukraine
miocen środkowy
sarmat
otwornice
formy aberrantne
rafy
paleośrodowiska
Ukraina
Opis:
The Middle Miocene (Upper Badenian) coralline algal reefs of Western Ukraine contain caverns (up to 1 m across) and fissures that are filled by Sarmatian deposits: marly clays, clayey carbonate sand and bioclastic, bryozoan-rich sand. These deposits often contain abundant and very well preserved calcareous benthic foraminifera; agglutinated forms have not been recorded. Foraminiferal tests quite commonly show morphological abnormalities, e.g. twin forms or tests with irregularities in size or shape in last chambers. Each of the three analysed samples is characterized by a different foraminiferal assemblage: Elphidium aculeatum assemblage, Hauerinidae assemblage and Lobatula lobatula assemblage. These assemblages are characteristic for a shallow marine environment. Low taxonomic diversity and high dominance or monospecific foraminiferal assemblages indicate generally a restricted marine environment. It seems that the increasing salinity and very high-energy environment were the most probable factors controlling the composition of the foraminiferal assemblages.
Górnobadeńskie rafy koralowe zachodniej Ukrainy posiadają kawerny o przekroju do 1 m oraz szczeliny, które obecnie są wypełnione osadami sarmackimi – iłami marglistymi i zasilonym piaskiem węglanowym i bioklastycznym, często mszywiołowym. Osady te często zawierają liczne i bardzo dobrze zachowane węglanowe otwornice bentosowe; nie stwierdzono natomiast otwornic zlepieńcowatych. Dość częste są skorupki z morfologicznymi nieprawidłowościami, np. formy bliźniacze albo skorupki z nieregularnością rozmiaru lub kształtu ostatnich komór. Każda z trzech próbek zawiera inny zespół otwornicowy: w pierwszej występuje zespół z Elphidium aculeatum, druga zawiera zespół z Hauerinidae, a trzecia – zespół z Lobatula lobatula. Wszystkie te zespoły są charakterystyczne dla środowiska płytkomorskiego. Niskie zróżnicowanie taksonomiczne i wysoka dominacja lub jednogatunkowe zespoły otwornicowe wskazują na ogólnie ograniczone środowisko morskie; wydaje się, że w takich warunkach najbardziej prawdopodobnym czynnikiem warunkującym skład zespołów otwornicowych było podwyższone zasolenie i środowisko bardzo wysokoenergetyczne.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2012, 449; 175-184
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Brzeżne facje badenu i sarmatu dolnego zbiornika przedkarpackiego w SE Polsce i zachodniej Ukrainie – wyniki badań ostatniego dwudziestolecia
Marginal facies of Badenian and Lower Sarmatian of the Fore-Carpathian Basin in SE Poland and western Ukraine – results of research during the last two decades
Autorzy:
Jasionowski, M.
Peryt, T. M.
Wysocka, A.
Poberezhskyy, A. V.
Powiązania:
https://bibliotekanauki.pl/articles/2062199.pdf
Data publikacji:
2012
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
sedymentacja klastyczna
sedymentacja węglanowa
gipsy
struktury sedymentacyjne
rafy
baden
sarmat
Roztocze
clastic sedimentation
carbonate sedimentation
gypsum
sedimentary structures
reefs
Badenian
Sarmatian
Opis:
Przedstawiono charakterystykę litologiczną utworów mioceńskich występujących na Roztoczu i terenach sąsiednich (zachodnia Ukraina). Utwory dolnobadeńskie rozpoczynają się transgresywnymi piaskami i piaskowcami kwarcowymi; w wyższej części obocznie przechodzą w margle i wapienie litotamniowe. Powstały w płytkowodnym, wysokoenergetycznym morskim środowisku sedymentacji, o zmieniającym się w czasie chemizmie wód. Środkowobadeński gips pierwotny tworzy szeroką brzeżną platformę siarczanową; w trakcie jego depozycji następowały znaczne wahania składu chemicznego solanek. W płytszych częściach zbiornika na gipsach występują utwory wapienia ratyńskiego, związane genetycznie z transgresją morską. W późnym badenie obszar Roztocza był strefą tranzytową dla materiału bioklastycznego i terygenicznego, w jej obrębie odbywało się przemieszczanie materiału ziarnowego związane z falowaniem i prądami wywołanymi przez falowanie oraz z ruchami masowymi. Węglany dolnosarmackie Roztocza cechują się nietypowym wykształceniem facjalnym oraz ubogim składem taksonomicznym organizmów, wskazującym na anomalne warunki środowiskowe – obniżone zasolenie wody i silne jej przesycenie względem węglanu wapnia.
Lithological characteristics of Middle Miocene strata of the Roztocze region (SE Poland and western Ukraine) is summarized. The Lower Badenian sequence begins with transgressive quartz sands and sandstones that subsequently are passing laterally into marls and coralline algal limestones. They originated in shallow-water, high-energy marine environment. The chemistry of waters at that time as well as during subsequent gypsum sedimentation fluctuated quite considerably. Middle Badenian gypsum deposits build a wide marginal sulphate platform. In shallower parts of the basin the Ratyn Limestone deposits cover gypsum; they are related genetically to new marine transgression. During the Late Badenian the Roztocze region was a transit zone for bioclastic and terrigenous material, and the grainy material was transported owing to waves and wave-generated currents as well as mass movements. The Lower Sarmatian carbonates of Roztocze show a typical facies and poor taxonomic composition of fossil assemblages that indicate abnormal environmental conditions – decreased water salinity and its oversaturation in respect to calcium carbonate.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2012, 449; 71--86
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
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